You can use the decimal module here:
>>> import decimal
>>> myothercontext = decimal.Context(rounding=decimal.ROUND_HALF_UP)
>>> decimal.setcontext(myothercontext)
>>> TWOPLACES = decimal.Decimal(10) ** -2
>>> decimal.Decimal('111.175').quantize(TWOPLACES)
Decimal('111.18')
>>> decimal.Decimal('1.175').quantize(TWOPLACES)
Decimal('1.18')
>>> decimal.Decimal('11.175').quantize(TWOPLACES)
Decimal('11.18')